Fallopian Metaplastic Papillary Tumour: An Atypical Transdifferentiation of the Tubal Epithelium?

A metaplastic papillary tumor of the Fallopian tube is an extremely uncommon condition, with odd and confusing features that make it difficult to categorize as benign or borderline. Here, we summarize all the published cases to date and document the case of a 41-year-old woman diagnosed with this alteration after her last childbirth and ensuing tubal ligation. One of the tubes was bulky and filled with a caramel-like substance encircling a blurry spot. Light microscopy detailed a slender stalk covered by eosinophilic, columnar plump cells, showing atypical nuclei and focal budding. Mitotic figures were absent. The immunohistochemistry panel was positive for pan-cytokeratin, epithelial membrane antigen, cyclin D1, and hormone receptors. Additionally, a proliferation index of less than 5% was rated using Ki-67. The true nature of this tumor (reactive vs neoplastic) is uncertain. Nonetheless, its association with pregnancy suggests an adaptive change, likely similar to the atypical transdifferentiation proposed for Arias-Stella reaction.

Pregnancy-Related Cytologic Changes In Cervicovaginal Smears / 대한세포병리학회지

Due to insufficient clinical information, most cervicovaginal smears from pregnant or postpartum women have been screened without regard to pregnancy-related cytological changes. Here, we have reviewed 116 abnormal cervicovaginal smears from 103 pregnant and postpartum women. Initial cytological diagnoses revealed the following: 9 cases of high-grade squamous intraepithelial lesions (HSIL), 8 cases of low-grade squamous intraepithelial lesions (LSIL), 85 cases of atypical squamous cells of undetermined significance (ASCUS), and 14 cases involving atypical glandular cells of undetermined significance (AGUS). 31 cases, upon review, involved pregnancy-related cytological changes, comprising 25 cases of decidua cells, 4 cases of Arias-Stella reaction, and 2 cases of decidual cells coupled with Arias-Stella reaction. Interpretation errors were detected in 14 cases: 13 cases of decidual cells interpreted as either ASCUS favor reactive or ASCUS ruled out HSIL, and one case of Arias-Stella reaction was interpreted as ASCUS ruled out HSIL. Decidual cells and degenerated glandular cells with Arias-Stella reaction can result in diagnostic mistakes. In order to avoid misdiagnosis and unnecessary surgeries, both clinicians and pathologists must be aware of the pregnancy-related cytological changes. The clinician should also always inform the pathologist on the pregnancy status of the patient.